EP0385571B1 - Electromagnetic induction heating apparatus - Google Patents
Electromagnetic induction heating apparatus Download PDFInfo
- Publication number
- EP0385571B1 EP0385571B1 EP90300628A EP90300628A EP0385571B1 EP 0385571 B1 EP0385571 B1 EP 0385571B1 EP 90300628 A EP90300628 A EP 90300628A EP 90300628 A EP90300628 A EP 90300628A EP 0385571 B1 EP0385571 B1 EP 0385571B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- coil
- temperature
- metal strip
- throat
- strip
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000010438 heat treatment Methods 0.000 title claims abstract description 69
- 230000005674 electromagnetic induction Effects 0.000 title claims description 11
- 239000002184 metal Substances 0.000 claims abstract description 131
- 229910052751 metal Inorganic materials 0.000 claims abstract description 131
- 230000006698 induction Effects 0.000 claims abstract description 37
- 230000033001 locomotion Effects 0.000 claims abstract description 15
- 239000004033 plastic Substances 0.000 claims abstract description 11
- 229920003023 plastic Polymers 0.000 claims abstract description 11
- 230000004044 response Effects 0.000 claims abstract description 7
- 239000004020 conductor Substances 0.000 claims description 37
- 238000012544 monitoring process Methods 0.000 claims description 36
- 239000000463 material Substances 0.000 claims description 28
- 238000000034 method Methods 0.000 claims description 22
- 230000001419 dependent effect Effects 0.000 claims description 14
- 230000003213 activating effect Effects 0.000 claims description 12
- 238000009529 body temperature measurement Methods 0.000 claims description 12
- 238000012806 monitoring device Methods 0.000 claims description 12
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- 239000000969 carrier Substances 0.000 claims description 8
- 230000000694 effects Effects 0.000 claims description 5
- 238000005259 measurement Methods 0.000 claims description 4
- 239000012809 cooling fluid Substances 0.000 claims description 3
- 230000000295 complement effect Effects 0.000 claims description 2
- 230000000750 progressive effect Effects 0.000 claims description 2
- 230000001360 synchronised effect Effects 0.000 claims description 2
- 238000009826 distribution Methods 0.000 abstract description 7
- 238000010030 laminating Methods 0.000 abstract description 3
- 239000000498 cooling water Substances 0.000 description 15
- 238000001816 cooling Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000007787 solid Substances 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 238000011065 in-situ storage Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 229920006254 polymer film Polymers 0.000 description 3
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
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- 238000002474 experimental method Methods 0.000 description 2
- 206010016256 fatigue Diseases 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 230000001464 adherent effect Effects 0.000 description 1
- 239000012790 adhesive layer Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 235000013361 beverage Nutrition 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 238000010891 electric arc Methods 0.000 description 1
- 239000011152 fibreglass Substances 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 239000004922 lacquer Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
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Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/10—Induction heating apparatus, other than furnaces, for specific applications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/10—Induction heating apparatus, other than furnaces, for specific applications
- H05B6/101—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces
- H05B6/103—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces multiple metal pieces successively being moved close to the inductor
- H05B6/104—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces multiple metal pieces successively being moved close to the inductor metal pieces being elongated like wires or bands
Definitions
- This invention relates to a method of and an apparatus for the electro-magnetic induction heating of metal strip material, particularly thin metal strip of rectangular transverse cross section, such as is used in the manufacture of metal cans for receiving and storing foods and beverages.
- Such a coating may comprise a lacquer, which is deposited on to the respective internal surfaces after the can parts have been shaped from flat metal strip, or on to thin metal strip that is to be used for making such can parts.
- the coating may comprise a film of a synthetic plastics material which is laminated with and bonded to metal strip that is to be used for forming the can parts.
- Such a film of plastics material has then to withstand the pressures and forces that have to be applied to the metal strip/film laminate in order to form the can parts therefrom. Hence, not only must the film material itself be able to withstand those deforming pressures and forces, but it must also remain firmly bonded at all parts thereof to the metal strip during the can forming processes.
- Bonding may be effected by the use of an adhesive layer between the metal strip and the plastics film, or by bonding the film material itself to the metal strip.
- the metal must be heated uniformly to a predetermined temperature (typically in the range 120°C to 300°C) at which the film may be applied to the heated metal strip. Bonding of the film material then takes place satisfactorily when the laminate (i.e. the metal strip and adherent film material) is reheated to a temperature typically between 200°C and 290°C depending on the particular polymer film being used.
- a predetermined temperature typically in the range 120°C to 300°C
- the most advantageous method employs high frequency electro-magnetic induction heating of the metal strip itself.
- the metal strip is heated directly, and selectively at its surfaces by circulating electric currents that are induced therein by an oscillating magnetic field, without the use of any intermediate agency for transferring heat to the metal surface.
- the temperature at which bonding of a film material takes place is somewhat critical, so that the metal surface must be evenly heated to the requisite temperatures (a) for example 120°C, in readiness for uniting the metal strip and film material at the time of pressing them into contact in the nip of a pair of pressure rolls, and subsequently (b) for example 250°C, to complete the bonding process of the united strip and film.
- metal strip suitable for can production is not entirely homogeneous in its composition (and thus, its physical characteristics), and moreover, the dimensions and shape of its transverse cross section can change within prescribed manufacturing limits (for example, at the centre of the strip +/- 8.5% of the nominal thickness, and at the sides of the strip 0 to -8% of the thickness at the centre).
- gauge variations in a strip can vary from strip to strip, and the strip can be wavy along its length (i.e. the strip is not truly flat).
- the metal strip be heated in such a way and at such a rate that the temperature of the heated metal (moving at a speed typically in the range 4 to 400 metres per minute) is substantially uniform, both across the width and along the length of the strip.
- Some known electro-magnetic induction heating systems involve passing a ferrous metal strip longitudinally through the throat of a multi-turn induction heating coil, of which the respective turns are of rigid construction, are rigidly supported in position, and have a predetermined fixed transverse cross-sectional shape suited to a particular strip to be heated. Moreover, such coils are cooled by passing cooling water through a cooling pipe which is secured in good thermal relation to the external surface of the conductor constituting those turns of the coil, so that the cooling of the conductor occurs indirectly by virtue of the transmission of heat through the wall of the cooling pipe.
- heating coils of such prior art systems have each been designed for specific sizes of metal strip, and cannot be readily adapted for use with any other size of metal strip.
- a collection of different heating coils has had to be stored for use when required with appropriate sizes of metal strip, and unavoidable down-time has occurred whenever a heating coil has had to be changed.
- British specification 1,522,955 discloses an induction heating system which operates in conjunction with a workpiece hot-drawing apparatus, with the objective of moving the induction heating coil progressively along the workpiece as the workpiece is progressively drawn by respective jaws thereby to increase its length.
- the process is applied to workpieces (e.g solid or hollow blades for a gas turbine) of varying, non-uniform transverse cross section.
- the induction coil has coil turns formed from a thin, flexible, flat strip material. That strip material is enclosed in an elastomeric sleeve through which cooling water flows directly in contact with the strip material.
- the coil turns are carried at circumferentially spaced positions by respective supports which are adjusted in position relative to the workpiece during the simultaneous heating and drawing processes by cam followers which cooperate with respective cams.
- the cams and cam followers are coupled to the respective jaws so as to change the shape of the coil turns as the jaws move apart.
- the objective of the system is to maintain a substantially constant distance between the induction coil and the surface of the workpiece, typically at "about three-sixteenths of an inch".
- the adjustment of the shape of the heating coil turns is carried out in a preset manner, and without reference to the actual temperature of the workpiece, or any part thereof.
- the present invention seeks to overcome the above-recited deficiencies of the prior art systems, and to provide an induction heating system which is both (a) readily adaptable so as to accommodate a wide range of metal strip sizes and materials, and (b) capable of producing in the outgoing metal strip a more uniform temperature distribution throughout both its transverse and longitudinal dimensions despite variations in the gauge, flatness, shape and position of the strip.
- a method of induction heating a moving elongate metal strip which method comprises the steps of:
- the method of the present invention may advantageously incorporate any one or more of the following optional features or steps:-
- the method of the present invention may advantageously incorporate any one or more of the following optional features or steps:-
- an electro-magnetic induction heating apparatus for induction heating a moving elongate metal strip, which apparatus comprises:
- the apparatus of the present invention may advantageously incorporate any one or more of the following optional features:-
- the induction heater 10 shown in the Figures 1 and 2 comprises a high frequency heating coil 12 constituted by a series of four spaced turns 14 of a rigid, solid electrical conductor, and having electrical terminals 16 located centrally and symmetrically of the coil. Secured to that conductor on the outside of the coil turns is a water cooling pipe 18 which is intimately secured to the conductor and has pipe connectors 20. Though shown separately, each such pipe connector 20 is usually integrated with the associated electrical terminal 16 for connection with a combined electric power and cooling water supply line. The turns of the coil are supported by support means (not shown) so as to be retained in their fixed configuration.
- a tube 22 of an electrically-insulating material (e.g. self-extinguishing fibre glass material) and a rectangular transverse cross section is supported by support means (not shown) in the throat of the coil 12 in axial alignment with the magnetic axis of the coil. That tube defines a tunnel 24 through which metal strip 26 to be heated is passed in a central position in the direction of arrow 28. That tube thus constitutes a mechanical and an electrical barrier for preventing contact of the metal strip 26 with the coil turns 14, as well as a thermal barrier.
- an electrically-insulating material e.g. self-extinguishing fibre glass material
- the terminals 16 of the coil are supplied with an appropriate high frequency electrical current (typically in the frequency range 50 Hertz to 500 kiloHertz) from a supply generator 30 thereby to induce eddy currents in the metal strip, and so heat it, as the strip is progressively advanced through the tunnel; and the water cooling pipe 18 is connected with a suitable source 32 of cooling water thereby to effect cooling of the coil turns 14 to a desired low operating temperature.
- an appropriate high frequency electrical current typically in the frequency range 50 Hertz to 500 kiloHertz
- Figure 2 shows in end view the dispositions and configurations of the metal strip 26, the tunnel tube 22 surrounding it, and the coil turns 14 encircling the tunnel tube.
- the metal strip 26 is shown as being of a nominally rectangular transverse cross section, and the coil turns are shown as being at all positions equidistant from the surface of the metal strip.
- the transverse cross sectional shape of the coil turns 14 (that is, of the coil throat 37) was modified in the manner shown in the Figure 3, so as to increase the distance of the side portions of the metal strip from the curved side portions of the coil turns 14, and so decrease the magnetic flux density in, and hence the heating of, those side portions of the metal strip.
- each adjustable brace or for each of a plurality of groups thereof) a closed loop control means for continuously (or continually) positioning it (or them) in dependence upon the deviation from a set reference level of a monitored local strip surface temperature.
- a closed loop control means for continuously (or continually) positioning it (or them) in dependence upon the deviation from a set reference level of a monitored local strip surface temperature.
- Such closed loop control means may respond to the output of a single temperature sensor positioned at a predetermined optimum position (e.g. a central position) relative to the width of the strip being heated, and maintain the sensed temperature in accordance with a set temperature reference signal.
- a predetermined optimum position e.g. a central position
- each such adjustable brace may be provided with its own individual temperature sensor located at a position corresponding to the position of the brace (or group of braces), and be controlled by its own associated closed loop means in response to the output of the associated temperature sensor.
- the various closed loop control means may be arranged to maintain the respective sensed temperatures in accordance with a reference temperature constituted by the temperature sensed at the central position on the metal strip.
- each such adjustable brace is carried by a pair of parallel links arranged so that the brace is constrained to move in a manner parallel to the metal strip being heated.
- the induction heater 10 is generally similar to that described earlier with reference to the Figures 1 and 2, in that it comprises a multi-turn coil 12 encircling an insulating tunnel tube 22 through which metal strip 26 is passed for eddy current heating.
- each of the five coil turns 14 comprises five similar, flexible copper conductors 38 (best seen in the Figure 7) which are connected electrically and mechanically in parallel at terminals 16. Those terminals are disposed close together (to reduce magnetic field leakage) and are connected to a high frequency A.C. supply source 30 via conductors 40, and to a cooling water supply source 32 via pipes 42.
- each such conductor 38 comprises a flexible, multi-strand cable of round cross section, and is enclosed within a flexible pipe 44 of relatively large bore 46.
- the pipe is made of an electrically-insulating plastics material.
- the end of each conductor 38 is secured in a cable socket 48 which has its larger tubular end 50 secured in a water-tight manner in the wall 52 of a tube 54 (of square cross section) constituting the terminal 16.
- each cable socket 48 is provided with a plurality of oblique ducts 56 for enabling the passage of cooling water through the socket to or from the insulating pipe 44 surrounding the conductor 38.
- the square terminal tube 54 carries at one closed end thereof a terminal stalk 58 on which is secured the electrical supply conductor 40, and adjacent that closed end a tubular coolant supply connector 60 to which is secured the water supply pipe 42.
- the coil turns 14 are braced together and supported at a plurality of positions spaced around the coil 12 by respective longitudinal braces 62, 64 which are themselves carried on a supporting framework 66.
- a supporting framework 66 For simplicity's sake, only relevant parts of that framework are shown in the drawings.
- braces 62 for supporting the sides of the coil turns 14 are fixed in position on the supporting framework 66
- the braces 64 disposed above and below the tunnel tube 22 are adjustably mounted on that framework in a manner permitting movement of the braces towards and away from the metal strip 26 being heated, thereby to allow adjustment of the transverse shape of the coil throat 37, and hence of the distribution of magnetic flux in the metal strip.
- Each adjustable brace 64 carries the respective multi-conductor coil turns 14 clamped between outer and inner brace members 68, 70, and is arranged for movement in a direction normal to the metal strip 26, (i.e. in a vertical direction as seen in the Figures 4 and 5) between vertical guide posts 72, 74 (forming part of the framework 66), being guided for movement therebetween by roller bearings 76, 78.
- Each such brace 64 is pivotally carried at the respective inner ends of two parallel links 80, 82 whose outer ends are pivotally carried on respective screw-threaded blocks 84, 86. Those blocks are themselves engaged on a screw-threaded driving shaft 88 which is supported in bearings carried in the respective guide posts 72, 74, and is coupled to an electric driving motor 90 (preferably of the stepper kind).
- the driving motor 90 and its associated driving shaft 88 constitute an actuator for adjusting the position of the brace 64 relative to the metal strip 26. Energisation of the driving motor is effective to move the two carrier blocks 84, 86 in concert along the driving shaft 88, and so rotate the parallel links 80, 82 about their pivotal connections on the brace 64. Since the brace is constrained against longitudinal movement by the vertical guide posts 72, 74, pivotal motion of the parallel links is effective to adjust the distance of the brace (and hence of the coil turns 14) from the metal strip 26, and hence the shape of the coil throat 37.
- Temperature sensors 92 are disposed above the metal strip 26, on the downstream side of the tunnel tube 22 and in alignment with the respective braces 64, and provide output signals dependent on the surface temperatures of the adjacent upper surface of the metal strip 26.
- Each driving motor 90 is energised by an associated closed loop control means 94 in accordance with the deviation of a temperature feedback signal provided by the associated temperature sensor 92 from a temperature reference level represented by a common reference signal provided by a manually adjustable temperature reference device 96.
- the adjustable braces (64) below the tunnel tube 22 may be controlled by their respective closed loop control means 94 in dependence upon the output signals of the temperature sensors 92, or alternatively, in dependence upon output signals provided by their own individual temperature sensors 98 mounted beneath the metal strip in corresponding positions across the width of the strip.
- the respective closed loop control means for driving the adjustable braces (64) carried below the tunnel tube may be dispensed with, and instead, the respective closed loop control means used for driving the respective braces above the tunnel tube may be used to drive in addition the corresponding adjustable braces carried below the tunnel tube.
- five (instead of four) adjustable braces 64 are provided above the metal strip 26, and the reference signal for the closed loop control means 94 of the central brace is provided by a manually adjustable temperature reference device, whilst the temperature reference signals for the closed loop control means of the other braces on the same side of the tunnel tube are provided by the output (feedback) signal of the central temperature sensor.
- the surface temperature of the metal strip is maintained across the width of the strip in accordance with the temperture sensed at the centre of the strip width, whilst the latter sensed temperature is controlled by the setting of the reference device.
- adjustable braces may be provided on the underside of the tunnel tube, and may be controlled in the same way as the arrangement above the tunnel tube 22, so as to facilitate bonding of a film material to the underside of the metal strip 26, as well as to the upper side thereof.
- the metallic parts of the framework 66, the braces 62, 64, and their adjustment means 80-88 are made of non-ferrous materials.
- the temperature sensing devices 92, 98 may be of any convenient kind, for example, of the thermo-couple variety, or the infra-red pyrometer variety. Moreover, whilst specific temperature sensing devices are used to measure the surface tempertures at specific positions across the width of the metal strip, as an alternative, a single temperature sensing device may be continuously traversed to and fro across the width of the strip so as to provide an output signal which represents the temperature at the instantaneous position of the sensing device. In that case, the output of the sensing device is repetitively sampled so as to provide sensed temperature signals corresponding to specific positions across the width of the strip.
- the terminal arrangement of Figure 8 may be modified by combining the terminal stalk 58 and its associated supply cable 40 with the cooling water connector 60 and its associated water supply pipe 42. Such a modified arrangement may be otherwise generally similar to that shown in Figure 8.
- FIG. 9 One terminal arrangement incorporating such a modification is shown in Figure 9.
- the terminal tube 54 is provided with an integral, tubular extension 100 (instead of the stalk 58), in which a tubular cable socket 102 is conductively secured, and around which a flexible, cooling water pipe 104 of an electrically insulating material is secured in a water-tight manner by a clip 106.
- a flexible, multi-strand electric supply cable 40 enclosed within the water pipe 104 is conductively secured in the convergent end part of the cable socket 102.
- Radial ports 108 formed in the cable socket 102 permit the passage of cooling water from the cooling water supply pipe 104 into the hollow terminal tube 54.
- That tube carries in its lower wall other tubular, metal extensions 110 in which other tubular cable sockets 112 are conductively secured.
- the respective flexible, multi-strand conductors 38 are conductively secured in the lower convergent parts of the respective cable sockets 112, and their respective enclosing cooling water pipes 44 are secured in a water-tight manner around the respective tubular extensions 110 by clips 114.
- Radial ports 116 formed in the cable sockets 112 permit the flow of cooling water from the terminal tube 54 into the cooling water pipes 44 which enclose the multi-strand conductors 38.
- each adjustable brace 64 is operated by two pivoted parallel links 80, 82, one of them could be omitted, and the other link connected to the brace at a more central position thereon.
- any other convenient means for moving the braces 64 in a parallel manner towards and away from the strip 26 may be used instead, and any other convenient form of motive power (e.g. hydraulic or pneumatic motors) may be used for operating the respective brace adjustment means.
- each brace may be provided with manual adjustment means (e.g. a winding handle or spanner) in addition to, or in substitution for, the driving motors and their respective control means, so as to provide an alternative manual mode, or a simple manual mode, of coil adjustment.
- manual adjustment means e.g. a winding handle or spanner
- Figure 10 shows for different positions across the transverse width of the metal strip 26 various temperature curves (profiles) indicating the manners in which strip temperature may vary across the strip width.
- Curve A shows a desired uniform temperature profile necessary for satisfactorily laminating the strip with polymer film.
- Curve B shows a typical non-uniform temperature profile which has been experienced with prior art arrangements, and which indicates the aforesaid rise in temperature at the edge portions of the strip.
- Curve C indicates a typical temperature profile which might otherwise be experienced in particular cases when the temperature-adjusted coil of the present invention is rendered inoperative.
- the principles of the present invention may be applied to any multi-turn induction heating coil, and to any such coil having any suitable number of adjustable braces for adjusting the coil throat characteristics.
- those principles may be applied to some only of the coil turns, which turns may, if desired, be braced together for simultaneous adjustment by respective adjustment means, the other coil turns being supported in a fixed configuration.
- the fixed (non-adjustable) coil turns may be made in the conventional manner from solid, copper conductor material of thin rectangular transverse cross section, wound in the manner illustrated in the Figure 1; whilst the adjustable coil turns are made of flexible, multi-strand cable of round transverse cross section in the manner of those shown in the Figures 4 to 9.
- the present invention provides in an induction heating coil a readily available, in situ adjustability of the coil throat characteristics to suit the dimensions, the transverse shape, and the magnetic and other relevant physical characteristics of the workpiece that is to be heated.
- the invention can be applied in other quite different fields of induction heating.
- the invention can be applied in an analogous manner to the heating of strip and sheet metals of much greater thickness, and to the heating of strip and sheet materials having more complicated transverse cross sectional shapes, for example, rolled metal beams of 'I' section.
- the heating system has been arranged to maintain across the transverse width of the workpiece a uniform temperature profile
- the system may be used in appropriate circumstances to maintain a desired non-uniform temperature profile across the workpiece width, by substituting for the single temperature reference device 96 a series of similar reference devices supplying to the respective control means 94 respective reference signals of different magnitudes.
- adjustability of the coil throat characteristics can be used in some cases solely to optimise and maintain a desired temperature profile for the workpiece to be heated, whilst in other cases, that adjustability may be used to provide the means for employing but one heating coil to heat various workpieces of widely differing characteristics, and also to provide for each such workpiece a suitable temperature profile.
- the invention can be applied to any form of multi-turn induction heating coil, regardless of its shape, size or configuration.
- the coil braces 64 and their respective actuating mechanisms are shown uniformly spaced with respect to the width of the metal strip 26, they may be positioned in any other desired way to provide optimum results. For example, braces nearer the edge portions of the metal strip 26 may be closer together than braces adjacent the central portion of the strip 26.
- the end braces 62 may be provided with actuating mechanisms similar to those of the braces 64, and be controlled in response to the output signals of temperature sensors 92, 98 appropriately positioned adjacent the edge portions of the metal strip.
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- General Induction Heating (AREA)
- Cookers (AREA)
- Lining Or Joining Of Plastics Or The Like (AREA)
- Shaping Of Tube Ends By Bending Or Straightening (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8902090 | 1989-01-31 | ||
GB898902090A GB8902090D0 (en) | 1989-01-31 | 1989-01-31 | Electro-magnetic induction heating apparatus |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0385571A1 EP0385571A1 (en) | 1990-09-05 |
EP0385571B1 true EP0385571B1 (en) | 1995-02-22 |
Family
ID=10650882
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP90300628A Expired - Lifetime EP0385571B1 (en) | 1989-01-31 | 1990-01-22 | Electromagnetic induction heating apparatus |
Country Status (13)
Country | Link |
---|---|
US (1) | US5055647A (xx) |
EP (1) | EP0385571B1 (xx) |
JP (1) | JPH0695474B2 (xx) |
KR (1) | KR900012509A (xx) |
AT (1) | ATE118954T1 (xx) |
AU (1) | AU632085B2 (xx) |
CA (1) | CA2008773A1 (xx) |
DE (1) | DE69017058T2 (xx) |
ES (1) | ES2068331T3 (xx) |
GB (2) | GB8902090D0 (xx) |
MY (1) | MY106684A (xx) |
PH (1) | PH27422A (xx) |
ZA (1) | ZA90433B (xx) |
Families Citing this family (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2262420B (en) * | 1991-12-03 | 1995-02-08 | Electricity Ass Tech | Induction heating apparatus |
US5308946A (en) * | 1992-02-06 | 1994-05-03 | Mohr Glenn R | Induction heating apparatus and method for heating metal strips and slabs |
CN1069070C (zh) * | 1993-12-16 | 2001-08-01 | 川崎制铁株式会社 | 金属板带的连接方法与连接装置 |
JP3127981B2 (ja) * | 1995-01-31 | 2001-01-29 | 信越半導体株式会社 | 高周波誘導加熱装置 |
US5739506A (en) * | 1996-08-20 | 1998-04-14 | Ajax Magnethermic Corporation | Coil position adjustment system in induction heating assembly for metal strip |
US6107613A (en) * | 1999-03-22 | 2000-08-22 | Ajax Magnethermic Corporation | Selectively sizable channel coil |
FR2808163B1 (fr) * | 2000-04-19 | 2002-11-08 | Celes | Dispositif de chauffage par induction a flux transverse a circuit magnetique de largeur variable |
US6576878B2 (en) * | 2001-01-03 | 2003-06-10 | Inductotherm Corp. | Transverse flux induction heating apparatus |
FR2852187A1 (fr) | 2003-03-07 | 2004-09-10 | Celes | Dispositif de chauffage par induction d'une bande metallique |
KR101016448B1 (ko) * | 2003-12-26 | 2011-02-21 | 재단법인 포항산업과학연구원 | 3상 유도가열 코일이 각각의 도금액 통로에 구비된 아연도금조의 유도가열장치 |
JP4295141B2 (ja) | 2004-03-12 | 2009-07-15 | 株式会社吉野工作所 | ワーク加熱装置及びワーク加熱方法 |
WO2008028005A2 (en) * | 2006-08-31 | 2008-03-06 | Duetto Integrated Systems, Inc. | Bond head assembly and system |
TW200812934A (en) * | 2006-08-07 | 2008-03-16 | Messier Bugatti | Method for densification of porous articles |
ATE456513T1 (de) | 2007-03-06 | 2010-02-15 | Huettinger Elektronik Gmbh | Flexibler induktor für das induktive versiegeln von gebinden |
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KR101464419B1 (ko) * | 2009-12-14 | 2014-11-21 | 신닛테츠스미킨 카부시키카이샤 | 유도 가열 시스템 및 유도 가열 장치의 제어 방법 |
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DE102013211291A1 (de) * | 2013-06-17 | 2014-12-18 | Siemens Aktiengesellschaft | Induktor zum Erwärmen von Objekten |
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WO2015114563A1 (en) * | 2014-01-31 | 2015-08-06 | Danieli & C. Officine Meccaniche S.P.A. | Apparatus for heating and transferring metal materials for a melting plant, and method for melting metal materials |
US11665790B2 (en) * | 2016-12-22 | 2023-05-30 | Whirlpool Corporation | Induction burner element having a plurality of single piece frames |
EP3580996B1 (en) * | 2017-02-08 | 2022-02-16 | Inductotherm Corp. | Adjustable transverse inductors for inductively heating strips or slabs |
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JP2020087734A (ja) * | 2018-11-27 | 2020-06-04 | 日本製鉄株式会社 | 鋼板用誘導加熱装置 |
JP6866410B2 (ja) * | 2019-02-20 | 2021-04-28 | 島田理化工業株式会社 | トンネル型加熱コイルを用いた誘導加熱方法 |
DE102019008622A1 (de) * | 2019-12-13 | 2021-06-17 | ABP lnduction Systems GmbH | Querfeldinduktionsheizeinrichtung |
CN112367728B (zh) * | 2020-10-28 | 2022-08-05 | 瓯锟科技温州有限公司 | 一种用于金属板带的电磁加热装置及其加热方法 |
CN112676342B (zh) * | 2021-01-22 | 2021-10-08 | 燕山大学 | 一种板材轧制过程加热装置及方法 |
CN114833206B (zh) * | 2022-05-25 | 2023-12-22 | 太原理工大学 | 一种用于超大h型钢轧制过程的电磁感应补热装置及方法 |
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FR1541924A (fr) * | 1967-10-26 | 1968-10-11 | Ajax Magnethermic Corp | Perfectionnements dans le chauffage par induction |
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FR2608347B1 (fr) * | 1986-12-11 | 1989-02-24 | Siderurgie Fse Inst Rech | Inducteur pour le rechauffage inductif de produits metallurgiques |
-
1989
- 1989-01-31 GB GB898902090A patent/GB8902090D0/en active Pending
-
1990
- 1990-01-19 AU AU48624/90A patent/AU632085B2/en not_active Ceased
- 1990-01-22 DE DE69017058T patent/DE69017058T2/de not_active Expired - Fee Related
- 1990-01-22 ES ES90300628T patent/ES2068331T3/es not_active Expired - Lifetime
- 1990-01-22 GB GB9001430A patent/GB2228166B/en not_active Expired - Lifetime
- 1990-01-22 MY MYPI90000107A patent/MY106684A/en unknown
- 1990-01-22 EP EP90300628A patent/EP0385571B1/en not_active Expired - Lifetime
- 1990-01-22 AT AT90300628T patent/ATE118954T1/de not_active IP Right Cessation
- 1990-01-22 ZA ZA90433A patent/ZA90433B/xx unknown
- 1990-01-29 CA CA002008773A patent/CA2008773A1/en not_active Abandoned
- 1990-01-30 US US07/472,027 patent/US5055647A/en not_active Expired - Fee Related
- 1990-01-31 JP JP2021903A patent/JPH0695474B2/ja not_active Expired - Lifetime
- 1990-01-31 PH PH39980A patent/PH27422A/en unknown
- 1990-01-31 KR KR1019900001068A patent/KR900012509A/ko not_active Application Discontinuation
Also Published As
Publication number | Publication date |
---|---|
DE69017058T2 (de) | 1995-06-14 |
GB2228166B (en) | 1992-07-29 |
ES2068331T3 (es) | 1995-04-16 |
JPH0695474B2 (ja) | 1994-11-24 |
GB8902090D0 (en) | 1989-03-22 |
ATE118954T1 (de) | 1995-03-15 |
JPH02297892A (ja) | 1990-12-10 |
AU632085B2 (en) | 1992-12-17 |
ZA90433B (en) | 1990-10-31 |
GB9001430D0 (en) | 1990-03-21 |
GB2228166A (en) | 1990-08-15 |
US5055647A (en) | 1991-10-08 |
AU4862490A (en) | 1990-08-09 |
EP0385571A1 (en) | 1990-09-05 |
CA2008773A1 (en) | 1990-07-31 |
MY106684A (en) | 1995-07-31 |
KR900012509A (ko) | 1990-08-04 |
PH27422A (en) | 1993-06-21 |
DE69017058D1 (de) | 1995-03-30 |
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